Hyper-V! Which version?

Posted on By Mark Wilson

I’ve written a lot about Hyper-V on this blog (some would say too much – I was recently accused of having lost all objectivity) but I’m going to carry on regardless. What I’ll try to do is steer clear of the arguments about how it competes with alternative technologies and stick to technical details. After all, this blog’s not really about news and comment – it’s supposed to be technical.

John Howard published a detailed blog post when Hyper-V RTMed but I’ve spent a fair amount of time recently clearing up confusion about the various versions of Hyper-V, so I’ll try and clarify things here:

Hopefully, that explains the various software products that include the Hyper-V branding or are in some way related to Hyper-V.

Configuring a Cisco IP phone for VoIP using SIP

Posted on By Mark Wilson

Cisco logoOne of my projects at home has involved trying to get a variety of telephony systems to work together so that I can make voice over IP (VoIP) or plain old telephone service (POTS) as necessary to get the best call rates. In truth, it’s probably not about getting the best rates as our phone bill is already pretty small – maybe it’s just because the geek inside me wants to get an IP phone working on my desk… anyway, I still have a few pieces of the puzzle to fit in place but last week I had a major breakthrough in getting a Cisco IP phone to provide a voice over IP (VoIP) service using SIP. It was a long haul, but worth it in the end – and this is how it’s done…

Cisco IP Phone 7940GFirst of all I needed an IP Phone. I managed to pick up a brand new 7940G for £50 on eBay (a bargain) and this was perfect for me. Why a Cisco phone? Partly because we use them at work (so I know they are good phones – and I like the form factor – although I wish it had a backlit screen) but mostly because there are so many of them about – that means that plenty of people have tried to do this and there is information available on the web. Using a Cisco phone does cause a couple of problems though:

  1. The standard protocol used for VoIP is session initiation protocol (SIP) and Cisco IP phones don’t use SIP natively. Cisco has it’s own IP Telephony system (Call Manager) which uses SCCP; however they do provide SIP firmware for their 79xx IP phones.
  2. Some of the Cisco documentation and software is only available with a service contract and generating configuration details can be a challenge if you don’t have access to a Cisco Call Manager solution – thankfully everything I used for this is available on the ‘net through a variety of websites that are aimed at getting people up and running with VoIP solutions.

It’s also worth knowing that there are two types of configuration file for Cisco IP Phones:

  • The 79x0 models use a fairly simple configuration file.
  • The 79x1 models use an XML configuration, which is all very well if you have access to a Cisco Call Manager solution but not so well documented if you don’t.

I found that the 7940 is a good model to go for as it has been around for a while, there is plenty of information available, and it can be picked up for a reasonably low price (and it helped to know that one of my colleagues already had this solution working well for him!). The 7960 is similar but with support for more lines and there are other models available (e.g. cordless phones, or phones with colour screens). In addition, Linksys (owned by Cisco) sells some similar phones that do run SIP natively but I don’t know if they use the same firmware.

After choosing the phone there were a couple of other considerations:

With the phone powered on and able to download a configuration, I uploaded the necessary configuration files to the TFTP server. Cisco Document ID: 5455 – Converting a Cisco 7940/7960 CallManager Phone to a SIP Phone and the Reverse Process gives details of the required files but the main ones to know are:

  • OS79XX.TXT – tells the phone which firmware to use.
  • SIPDefault.cnf – configuration information relevant to all phones.
  • SIPmacaddress.cnf – configuration information relevant to a specific phones.

Other files that I have include:

  • RINGLIST.DAT – Lists audio files that provide the custom ring types.
  • CTU.raw – an audio file referenced by RINGLIST.DAT.
  • dialplan.xml – a dialplan.
  • Various firmware images named as follows:
    • P003x-xx-x-00.bin – universal application loader for upgrades from images earlier than 5.x.
    • P003x-xx-x-00.sbn – secure universal application loader for upgrades from images 5.x or later.
    • P0y3x-xx-x-00.loads – universal application loader and application image, where y represents the protocol of the application image (.loads) file: 0 for SCCP, and S for SIP.
    • P0y3x-xx-x-00.sb2 – application firmware image, where y represents the protocol used by the image: 0 for SCCP, and S for SIP.

With all the necessary files available on the TFTP server, I set about upgrading the firmware to the latest SIP release by editing the OS79XX.TXT file to read P0S3-08-2-00 and resetting the phone. The TFTP server log told me that the phone picked up the appropriate firmware release, but that it couldn’t find one of binary images (P0S3-08-2-00.bin)

After some research, it seems that POS3-08-x-00.bin does not seem to exist for any 8.x firmware:

Versions [6.x] and [7.x] seem to have P0S3-0x–xx-00.BIN files which make it easy when upgrading from SCCP to SIP as all you have to do is rename the file it loads in OS79XX.TXT to one of these *.BIN files and its all done straight to SIP.

With version 8 series it doesn’t have these and that forces you to upgrade it in a 3 part reboot and load phase with[:]

XMLDefault.cnf.xml
[SEPmacaddress.cnf.xml]

That loads the *.loads file then it loads *.sbn and reboots
After warm reboot it loads *.sb2 which must be the sip software.

Then reboots again starting in sip and then provisions with[:]

SIPDefault.cnf
[SIPmacaddress.cnf]

Armed with this new information, I put the 7.4 SIP firmware into my TFTP root folder, edited OS79xx.TXT to read P0S3-07-4-00 and created an xmlDefault.CNF.XML file.

After booting the phone I was pleased to see a message that said Upgrading software but that pleasure soon ended as the upgrade never completed. Thankfully I hadn’t “bricked” the phone and, after another reboot, the phone showed a message which said Load ID Incorrect. The TFTP logs indicated that the phone was trying to load a file called SEPmacaddress.cnf.xml.

Googling turned up some more information and it turned out I was trying to go too far in one jump – my phone had been supplied with v3.x SCCP firmware and I was trying to go straight to v7.x firmware:

You have to upgrade to a new version of SCCP or older version of SIP before the bootloader on the phone will be able to handle the newer firmware […] you can either use an older version of SIP first, or a newer version of SCCP. Older SIP is probably easier – 6.3 is the newest you can use to then jump to 7.x and/or 8.x.

I put the v6.3 firmware on my TFTP server, edited OS79XX.TXT to read P0S3-06-3-00 and rebooted the phone. This time I saw the Upgrading Software message and watched the transfer take place.

After rebooting itself the phone came back up on the v6.3 firmware and was showing itself as Phone Unprovisioned.

I set about the second stage upgrade to v8.2 by editing OS79XX.TXT to P0S3-08-2-00 and rebooting the phone again. That didn’t help, but a further OS79XX.TXT edit from P0S3-08-2-00 to P003-08-2-00 did the trick as the Universal Application Loader booted.

Despite attempting to read non-existent files called CTLSEPmacaddress.tlv and SEPmacaddress.cnf.xml (the Cisco 7940 and 7960 IP Phones Firmware Upgrade Matrix explains the hunt algorithm employed by the Universal Application Loader) the phone downloaded the appropriate files and restarted to return as an unprovisioned device, finally running the v8.2 SIP firmware.

By this point, the TFTP logs were not much help as they didn’t indicate any errors but the status message on the phone gave me more clues:

W350 unprovisioned proxy_backup
W351 unprovisioned proxy_emergency
W362 No Valid Line Names Provisioned

The unprovisioned backup and emergency proxies didn’t bother me but I couldn’t understand why I had no valid lines provisioned. I had been trying to get the phone to use my Linksys SPA3102 as a SIP proxy but something was not quite right. In the end, I gave up and registered with SIPgate. After updating my configuration files to reflect the SIPgate account details, my phone picked up a valid line but couldn’t make or receive calls. Following advice on the SIPgate website, I made sure that the following ports were all open:

I’m not sure if all of these are strictly necessary but they seem to have got things working. The final contents of my configuration files are detailed below, after the TFTP log from a successful boot:

Connection received from ipaddress on port 50967 [25/07 00:41:32.672]
Read request for file <CTLSEPmacaddress.tlv>. Mode octet [25/07 00:41:32.672]
File <CTLSEPmacaddress.tlv> : error 2 in system call CreateFile The system cannot find the file specified. [25/07 00:41:32.672]
Connection received from ipaddress on port 50968 [25/07 00:41:32.703]
Read request for file <SEPmacaddress.cnf.xml>. Mode octet [25/07 00:41:32.703]
File <SEPmacaddress.cnf.xml> : error 2 in system call CreateFile The system cannot find the file specified. [25/07 00:41:32.703]
Connection received from ipaddress on port 50969 [25/07 00:41:32.719]
Read request for file <SIPmacaddress.cnf>. Mode octet [25/07 00:41:32.719]
Using local port 1203 [25/07 00:41:32.719]
<SIPmacaddress.cnf>: sent 2 blks, 632 bytes in 0 s. 0 blk resent [25/07 00:41:32.735]
Connection received from ipaddress on port 50970 [25/07 00:41:32.766]
Read request for file <P0S3-08-2-00.loads>. Mode octet [25/07 00:41:32.781]
Using local port 1204 [25/07 00:41:32.781]
<P0S3-08-2-00.loads>: sent 1 blk, 461 bytes in 0 s. 0 blk resent [25/07 00:41:32.781]
Connection received from ipaddress on port 50962 [25/07 00:41:54.672]
Read request for file <SIPDefault.cnf>. Mode octet [25/07 00:41:54.672]
Using local port 1205 [25/07 00:41:54.672]
<SIPDefault.cnf>: sent 2 blks, 925 bytes in 0 s. 0 blk resent [25/07 00:41:54.688]
Connection received from ipaddress on port 50963 [25/07 00:41:54.813]
Read request for file <SIPmacaddress.cnf>. Mode octet [25/07 00:41:54.828]
Using local port 1206 [25/07 00:41:54.828]
<SIPmacaddress.cnf>: sent 2 blks, 632 bytes in 0 s. 0 blk resent [25/07 00:41:54.828]
Connection received from ipaddress on port 50967 [25/07 00:41:56.891]
Read request for file <RINGLIST.DAT>. Mode octet [25/07 00:41:56.891]
Using local port 1207 [25/07 00:41:56.891]
Connection received from ipaddress on port 50974 [25/07 00:41:56.907]
<RINGLIST.DAT>: sent 1 blk, 15 bytes in 0 s. 0 blk resent [25/07 00:41:56.907]
Read request for file <dialplan.xml>. Mode octet [25/07 00:41:56.907]
Using local port 1208 [25/07 00:41:56.907]
<dialplan.xml>: sent 1 blk, 104 bytes in 0 s. 0 blk resent [25/07 00:41:56.907]

OS79XX.TXT

P003-08-2-00

SIPDefault.cnf

;begin
image_version: P0S3-08-2-00
proxy_register: 1
dial_template: dialplan
tftp_cfg_dir: “”
sntp_server: “ntp.sipgate.net”
sntp_mode: unicast
time_zone: GMT
dst_offset: 1
dst_start_month: March
dst_start_day_of_week: Sun
dst_start_week_of_month: 8
dst_start_time: 01
dst_stop_month: Oct
dst_stop_day_of_week: Sun
dst_stop_week_of_month: 8
dst_stop_time: 02
dst_auto_adjust: 1
time_format_24hr: 1
date_format : D/M/Y

# NAT/Firewall Traversal
nat_enable: 1 ; 0-Disabled (default), 1-Enabled
nat_address: “” ; WAN IP address of NAT box (dotted IP or DNS A record only)
voip_control_port: 5060 ; UDP port used for SIP messages (default – 5060)
start_media_port: 8000 ; Start RTP range for media (default – 16384)
end_media_port: 8012 ; End RTP range for media (default – 32766)
nat_received_processing: 0 ; 0-Disabled (default), 1-Enabled
outbound_proxy_port: 5082
telnet_level: 2
;end

SIPmacaddress.cnf

;begin
image_version: P0S3-08-2-00
phone_label : “markwilson.it ” ; Has no effect on SIP Messaging
line1_name : “sipgateid” ; SIPgate device ID#
line1_authname : “sipgateid” ; SIPgate device ID#
line1_password : “sipgatepassword” ; SIPgate device password
line1_shortname : “phonenumber”
line1_displayname : “phonenumber”
proxy1_address : “sipgate.co.uk”
proxy1_port : 5060
line2_displayname: “”
line2_shortname: “”
line2_name: UNPROVISIONED
line2_authname: “UNPROVISIONED”
line2_password: “UNPROVISIONED”
proxy2_address : “”
proxy2_port : 5060
phone_password: “password”
logo_url: “http://webserver/sipgate.bmp”
directory_url: “http://webserver/directory.xml”
;end

RINGLIST.DAT

CTU CTU.raw

xmlDefault.CNF.XML





2000
2427 2428



P0S3-07-4-00






Further information

Here are some of the sites that I found particularly useful as I went through this process:

[update 10 September 2009: Here’s another useful resource on how to set up a cisco 7940 and 7941 IP phone to do SIP.]

[update 27 March 2010: Tyler Winfield’s article on configuring Cisco IP phones with Asterisk is very thorough and easy to read – even if you’re not using Asterisk.]

ESX for free… but is it really?

Posted on By Mark Wilson

Starting from today, VMware’s ESXi hypervisor will be offered free, supposedly to counter the threat from Microsoft Hyper-V and there is an interesting article over at virtualisation.info. But dig a little deeper and, as James Staten at Forrester Research notes:

“This doesn’t really address the typical enterprise’s cost of VMware deployment – just the marketing threat of the low Hyper-V starting price.”

James’s article on the release of “free” ESX is worth a read – he continues by noting that:

“VMware has used this pricing strategy several times to help seed the market, grow its customer base and fend off competitors. VMware Player and GSX server were both made free to respond to the threat of open source and other competitors. Both Player and GSX served as nice onramps to try VMware but had performance penalties and limitations, so customers quickly upgraded when they were through experimenting – stopped a lot of customers from experimenting with the open source stuff. The same is likely to be true here; while free ESXi certainly isn’t crippled (it’s the same code as in the commercial versions) the fact that you can’t manage more than one at a time is the driving drawback.”

But the part I struggle with in James’ analysis is the the summary:

“If you want a more mature solution and the live migration and HA capabilities VMware brings to the table, the cost differential is worth it.”

Is it? Is anybody really failing live production workloads over between hosts using VMotion? Not with the change control processes that most of my customers use. That’s why Microsoft’s quick migration is fine for controlled fail-over – a few seconds of outage is generally not a concern when you have already scheduled the work. As for high availability, I can provide a highly available Hyper-V cluster too. Then there is maturity… VMware may have invented the x86 virtualisation space but dealing with the company can sometimes be difficult (in fairness, that criticism can be levelled at other organisations too).

There’s an old adage that no-one got fired for choosing IBM. More recently no-one got fired for choosing HP (formerly Compaq) ProLiant servers. In the virtualisation space no-one gets fired for choosing VMware – not at the moment anyway – at least not until the CFO finds out that you could have implemented the solution using Microsoft technologies for less money. For that matter, when did anyone get fired for choosing Microsoft?

Creating a photographic image with high dynamic range

Posted on By Mark Wilson

Last year I wrote about the concept of making photographic images – not just taking them and my recent holiday in France was a perfect opportunity to reconnect with my photographic hobby and attempt to make some good landscape images.

I’d also been hearing a lot on the This Week in Photography podcast about the concept of high dynamic range (HDR) images (see TWiP episode 9), where multiple exposures are combined so that one or more shots exposed for the highlights are combined with others that make the most of the shadows and I decided to give that a try.

We were staying in a very attractive area of north-west France РTr̩vignon in Bretagne (Brittany) Рand I found myself inspired to take photographs around the small port at Pointe de Tr̩vignon. Thankfully, I have a very understanding (and patient) wife, as it took several attempts to get the image that I was looking for.

On the first evening, I went down to the harbour and took some photos. They were okay but nothing stunning. Even so, I discovered a couple of basic points that would help me out on future visits:

  • It’s really difficult for Photoshop to merge images that involve boats floating on water… the boats move so the images can’t be aligned (I felt such an idiot for not thinking of that one)!
  • If you take a set of images adjusting the aperture and the shutter speed then the two cancel one another out and what you end up with is a set of identically exposed images with a varying depth of field (that’s basic stuff from a photography 101)! In the end I settled on using either the camera’s auto-bracketing functionality (which will give me three shots at the chosen exposure interval) or, if I wanted more than three images to merge, shooting on aperture priority with manual focus and then adjusting the shutter speed to bracket the exposures (effectively fixing the focus and depth of field, then adjusting the exposure length to control the light entering the camera).

The next night I went out a bit later – I thought I’d try and catch the sunset. I tried some different sections of the coast to try and get the sun over the sea with some rocks for foreground interest (no boats this time!) but it wasn’t really working out. I’d also got my calculations wrong for when the sun would be setting and in the end I gave up waiting and went back to the house. Sometimes, you just have to accept that the ingredients for a good photo are not all there.

On the third day I had the location sorted (back to Pointe de Trévignon) and went out a bit later in the evening. I watched the sun set for an hour which was beautiful, but I still didn’t think I had the best shots. I was just about to give up when the sun finally set and – Wow! – suddenly the sky had changed and the photographic possibilities opened up to me. In the half hour after sunset I took a shot a lot of images.

This image is one of my favourites from that third night:

Pointe de Trévignon HDR

Taken about 30 minutes after sunset, the sky has begun to fade slightly but there is still plenty of colour. I’ve combined exposures taken at 0EV, -1EV and -2EV to create an HDR image then dropped back to 16-bit mode to apply a Photoshop Velvia action before finally straightening the image, cropping and saving as an 8-bit JPEG. Incidentally, I first did this in Photoshop CS2 on the Mac and the process introduced quite a bit of digital noise – switching to Photoshop CS3 seems to have corrected that problem.

As can be seen from the non-Photoshopped original images below, even without the HDR, underexposing by 1-2 stops seemed to work well (from memory, I probably used a 0.6ND graduated filter to tone down the sky too) but, whilst the the -2EV shot has plenty of sunset detail, it has silhouetted the lighthouse and rocks. The -1EV shot is balanced, but the foreground is still a little on the dark side, whilst the 0EV shot has started to burn out the sky. By merging the three shots I managed to keep both the shadow detail and the highlights and the 6 second exposure from the 0EV shot shows the movement of the water on the exposed side of the harbour wall.

Original images used to create Pointe de Trévignon HDR

The lesson for me was that I needed to work to find the right location and lighting and, importantly, it was only when I was in the right frame of mind and was excited by the natural world around me that I started to see the real photographic opportunities.

“I often think of that rare fulfilling joy when I’m in the presence of some wonderful alignment of events.

Where the light, the colour, the shapes and the balance all interlock that I feel truly overwhelmed by the wonder of it”

[Charlie Waite]

It took three visits before I got the right shots to make this image. Only once I’d fully engaged with the natural world and immersed myself in the environment around me could I unlock the photographic potential of the scene to create some technically correct images that were then combined to make something creatively pleasing.

Of course, there are some who have both the skills and the experience to just know what works and what doesn’t and they might get it right first time. I’m pretty pleased with the final result but it’s far from perfect. I need to get out more and learn what works and what doesn’t. Even after 25 years-or-so of taking photographs, I have too strong a bias towards the technology and I need to work on the creative site of things. I also need to play around a bit more with Photoshop’s HDR capabilities (or possibly some alternative packages) and see how I can gain more control over how the images are merged. For a first attempt at creating an HDR image this is not too bad but professional landscape photographers like Joe Cornish and Charlie Waite have nothing to fear from me just yet!

It goes all the way up to 11

Posted on By Mark Wilson

There’s a well-known phase used to describe things that go one better – they go up to eleven – and the idiom originates from the cult film “This is Spinal Tap” (which I really must watch one day…). Well, clearly someone at the BBC has a sense of humour as I noticed tonight that the volume control on the BBC’s media player for online viewing maxes out at, not 10, but 11.

BBC Media Player volume goes to eleven

How much electricity does your home IT use?

Posted on By Mark Wilson

Last month I commented on minimising man’s effect on the planet and, whilst I’m in favour of reducing carbon emissions, much is being made of a few high-profile but relatively low-impact issues and governments are doing little to tackle the little things that can really make a difference.

One of those things we can all do is to examine the amount of electricity that we use – because there is direct link between electricity generation and carbon emissions (and, here in the UK, we have precious-little hydro- and solar-powered infrastructure so much is being made of wind, which is inefficient and variable, so still needs to be backed up with a firm source of energy – generally coal, gas or nuclear).

I imagine that, as IT administrators and enthusiasts, many of this blog’s readers have a collection of devices running a home IT infrastructure that would be more suitable for a small business. Back in January I bought a small server to migrate the workload away from my many PCs but my (capped rate) electricity bill has still risen – largely because I haven’t yet managed to move the workload away from the old kit that is destined to be turned off. Even if you don’t have a stack of IT kit running in your garage/cupboard-under-the-stairs-which-acts-as-the-home-data-centre, the chances are that you work from home sometimes – saving money and the reducing the emissions caused by travel – but distributing your employer’s energy usage across many homes (meanwhile the lights are still on and the air-con is still running back in the office).

So how much power does your IT use? Well, armed with a simple power monitor from Maplin, this is what I found:

Device Power (“on”) Power (“off”) Power (“standby”)
10 year-old PC (Compaq DeskPro EN6350: Pentium 3, 512MB RAM, 20GB HDD) 44W 5W
5 year-old PC (Compaq Evo D500: Pentium 4 1.7GHz, 512MB RAM, 20GB HDD) 50-100W 3-4W
Modern notebook PC (Apple MacBook: Intel Core 2 Duo 2.2GHz, 4GB RAM, 320GB HDD) 22W 1W
Server (Dell PowerEdge 840: Quad-core Intel Xeon 2.13GHz, 8GB RAM, 1.1TB storage) 100W 10W
15″ LCD Monitor 25W 1W 1W
20″ LCD monitor 42W 2W 2W
Inkjet all-in-one printer/fax/scanner/copier (HP OfficeJet 6310) 8W (16W when printing)
Laser printer (HP LaserJet 2200dn) 10W (600W when printing)
Fast Ethernet Switch (3Com 3300) 45W
Gigabit Ethernet Switch (Cisco 3750) 65W
Unmanaged Ethernet hub (NetGear EN108) 2W
Unmanaged Gigabit Ethernet switch (NetGear GS108) 5W
Desk lamp 25W 1W
Nokia mobile phone charger 3W 0W
24″ CRT Widescreen TV 80W (average) 2W 4W

MaplinI’m no electrical engineer but there are some surprises there for me. My mobile phone charger doesn’t use any power when it’s not charging (contrary to popular belief) but it seems my desk lamp does! Turning off my monitors at night seems to make no difference to their power draw, so I should really remove the plug from the socket (as should I for the TV). Meanwhile my recent switch from a laser printer to an inkjet might save some power (depending on the amount of printing I do) but what about the environmental cost of all those ink cartridges? As for the networking kit – my unmanaged switches are not only fanless (i.e. silent) but they use significantly less power too.

Of course, not all devices are equal. When I last visited my Grandmother, I was alarmed to find that her television was still “on” when it was on standby – the screen was off but I could still hear the sound being broadcast on the last channel she had been watching. And my 10-year-old Sony Trinitron Widescreen CRT TVs are probably more efficient than today’s 100Hz High Definition LCD displays – they’ll probably last longer too, which is why I’m not getting rid of them just yet.

As for that pile of PCs running a “data centre” in the garage, it seems that my new server is reasonably efficient in comparison but it will still draw 2.4kWh a day – at around £0.15 per unit (it’s not that simple because some units are charged at a lower rate than others) that’s costing me £0.36p a day. That doesn’t sound much until you realise that works out as £131 a year if the server is running 24×7 – and that equates to 0.377 tonnes of CO2 [source: Carbon Footprint]. It looks like I’d better get out and plant some more trees…

So, regardless of whether or not you believe in “green IT”, you can save some money by switching off some of this kit when it’s not in use. Modern operating systems have power-saving options – and technologies like Wake On LAN (WOL) allow us to bring a device back online when it is required. You need to apply some common sense too – turning off the VCR at the mains socket won’t let the device do what it is intended to do (i.e. record TV programmes) but does the microwave in the kitchen need to be on all the time just to run a digital clock (another 2W)?

If you can’t get your head around saving the planet – forget the “greenwashing” and think about saving some money instead.

Calling all photographers – stand up for your rights

Posted on By Mark Wilson

For a while now, it’s become increasingly difficult to take photographs without suspicion and stories like the one of the father-of-three who was branded a pervert for photographing his own children in public park are extremely alarming. Admittedly this story was reported in the Daily Mail (a fine example of balanced reporting – not!) but nevertheless it is a perfect example of political correctness gone mad.

I’m a parent too and I have to admit that I am always very self-conscious when I photograph my children playing with their friends. Thankfully, their parents take no issue (indeed some find it strange that I even check with them first). I even have some great pictures of my kids that were taken by other people. But unfortunately it’s all too easy to accuse someone of wrong-doing – generally being a pervert or a terrorist – and the authorities will generally act first and reason later.

There are very few restrictions on taking photographs in public places but it won’t take long for that to change. Indeed, the current UK Home Secretary, Jacqui Smith has stated in a letter to the National Union of Journalists that:

“[…] there is no legal restriction on photography in public places […and…] there is no presumption of privacy for individuals in a public place.”

That’s sounds good until she continues by writing:

“Decisions may be made locally to restrict or monitor photography in reasonable circumstances. That is an operational decision for the officers involved based on the individual circumstances of each situation.”

Basically, she’s said that it’s not illegal but that the authorities will act if they feel it is appropriate and that, even though Chief Constables will issue guidance, the decision is down to local officers.

I spent a large chunk of my formative years watching trains and, whilst I realise that the social stigma that is attached to such activities will make readers think I’m weird now, that’s practically outlawed these days (the police will soon move people on who are seen hanging around a major railway station). Then, when I flew to the States last year, I took some pictures of aeroplanes at Heathrow (my young son has only seen them high in the sky – he had no idea what the plane Daddy was going to fly on looked like) – thankfully no-one tried to stop me but it won’t be long before that is considered a security risk.

The UK Government’s petitions site is little more than a publicity exercise but nevertheless it is an opportunity to demonstrate the strength of public feeling on this. If you are a UK citizen and you would like to see a public statement on clarifying the law as it relates to photography then I urge you to sign the e-petition on Photography Law:

Through history, we have documented the world around us, whether through written word, art or photography.

Photography in particular has provided fantastic insights into the past and present, and is a hobby enjoyed by millions of people worldwide.

But today, it’s becoming increasingly difficult to take photos of our surroundings, particularly in cities like London.

In recent years, the price divide between professional and consumer equipment has blurred, and it’s quite common these days to see amateurs and hobbyists carrying around tripods, SLR cameras and a backpack full of equipment.

Yet, we are constantly harrassed [sic] by security guards and police officers in the name of preventing terrorism. They seem to be operating under a different interpretation of the law to the rest of us, believing that somehow the length of your lens, or size of your camera is relevant.

We would like clarification by the goverment [sic] on the law regarding photography of buildings and landmarks from public locations.

If you don’t, then you’ll only have yourself to blame when the current power-hungry administration forces through the next phase of nanny state laws that restrict an individual’s ability to capture a photograph in a public place.

Windows Server User Group UK on LinkedIn

Posted on By Mark Wilson

LinkedIn logoLast year, Scotty McLeod set up the Windows Server User Group UK with the intention of creating a lively discussion area (backed up with regular meetings) for UK-based IT Professionals who are interested in the development of the Windows Server platform. Unfortunately, Scotty was involved in a serious accident at the start of the year and, whilst he is making a fantastic recovery, it’s going to take a while longer yet.

With no administrative access to the user group website, we have no way of finding out who our members are and no way to contact each other should we do what we talked about at the community day in April (was that really 3 months back?) – namely to start to organise some events. So, I’ve created a LinkedIn group to supplement the user group website. If you’re interested in Windows Server and would like to take part in future user group events, please join the Windows Server User Group UK on LinkedIn.

Once we have a quorum, then I’ll be in touch to try and get the ball rolling for some meetings.

Comparison between Hyper-V and the Xen hypervisor in RHEL

Posted on By Mark Wilson

Even though choosing a hypervisor is only a small part of implementing a virtualisation strategy, much has been written about how Microsoft Hyper-V compares to VMware ESX – and there are some fundamental differences between those two products. Architecturally, Hyper-V has a lot more in common with the Xen hypervisor (although they are not identical) and indeed XenSource worked with Microsoft to provide Linux support for Hyper-V and I’ve recently been alerted to the presence of a short white paper which compares Hyper-V and the Xen technology implemented in Red Hat Enterprise Linux (the leading Linux distribution, which is not currently on the list of supported guest operating systems for Hyper-V). Despite being published by Microsoft, it seems to me to give a balanced view between the two products, although it should also be noted that Red Hat has announced it will be switching from Xen to KVM for future virtualisation support.